Power surfacing means



Nov. 1, 1955 Filed Aug. 5. 1954 F. D. DOLAN ETAL 2,722,091

POWER SURFACING MEANS 2 Sheets-Sheet l INVENTOR? 00/40 BY war/es A. Aaf/mer ATTORNEYS Nov. 1, 1955 F. D. DOLAN ETAL 2,722,091

POWER SURFACING MEANS Filed Aug. 5, 1954 2 Sheets-Sheet 2 1 v VENTOR.

Franc/5 0. 00/00 BY Char/es Alaflmcr 1E1.

ATT'O RNEYS United States Patent POWER SURFACING MEANS Francis D. Dolan and Charles A. Latimer, Toledo, Ohio, assignors to The American Floor Surfacing Machine Company, Toledo, Ohio, a corporation of Ohio Application August 5, 1954, Serial No. 447,961

4 Claims. (Cl. 51-170) This invention relates particularly to portable hand sanding and abrading machines referred to generally in the trade as bench-type sanderplanes.

The primary object of the invention is the provision in a machine of this character, of novel tensioning means for the abrading belt which is easily and quickly operated to apply the desired working tension to an associated belt when it has been mounted on the spaced guiding rolls and also to release the belt tension to facilitate removal of the belt from the rolls.

Further objects and advantages of the invention will be apparent from the following detailed description, and from the accompanying drawings illustrating one embodiment of the invention, and in which- Figs. 1 and 2 are opposite side views of a center plane embodying the invention;

Fig. 3 is a section on the line 33 in Fig. l, with parts broken away;

Fig. 4 is a section on the line 44 in Fig. 3;

Fig. 5 is an enlarged section on the line 55 in Fig. 4, and

Fig. 6 is a cross-section on the line 66 in Fig. 5.

Referring to the drawings, 1 designates a sanderplane housing having at one side a dependent bottom flange 2 forming one side wall of a bottom space in which the customary sanding belt 3 and its guide rolls 4 and 5 are positioned. The drive roll 4 is suitably driven from a motor in the housing 1 and has its carrying shaft 6 journaled adjacent to one end in a suitable bearing in the flange 2. The customary pressure plate 7 for the lower run of the belt is carried by the side flange 2 above such run.

The mounting means for the idler roll 5, and in which the present invention resides, includes a channel guide 10 disposed lengthwise between the two rolls 4 and 5 and fixedly secured by screws 11 to bosses 12 projecting inwardly from the housing flange 2 (Fig. 3). The guide 10 is substantially centrally disposed in the space between the two rolls transversely of such space, and its outer side, relative to said space, is closed by a plate 13 secured by screws 14 to laterally projecting edge flanges 15 on the free side wall edges of the guide. The end of the guide 10 toward the idler roll 5 is open.

The idler roll 5 is mounted in the fork of a U-shaped yoke 18 and the cross or loop member of this yoke is pivotally connected centrally of its ends by a pin 19 to a frame or cross-head 20, thus permitting rocking of the yoke in a plane parallel to the roller axis so as to effect a tracker adjustment of the belt thereon, as well understood in the art. The yoke is biased to normally swing in one direction relative to the frame 20 by a spring 22 which encircles the pivot pin 19 and has opposite ends bearing outward against the yoke and frame, as shown in Fig. 5.

The frame 20 has an arm 23 carrying a screw 24 with its axis transverse to that of the pivot pin 19, and this screw has a tapered end engaging the yoke and adapted when turned in the frame arm to act in the manner of a 2,722,091 Patented Nov. 1, 1955 wedge against a side portion of the yoke to turn it against the pressure of the spring. This provides a very delicate adjustment for the yoke. This screw is turned from the outer side of the flange 2 and its stem projects freely through a longitudinally extending slot 24 in the flange (Fig. 2), thus allowing for adjustment of the frame 20 and parts carried thereby relative to the housing.

The frame 20 has a bar-like stem 26 projecting therefrom transverse to the pivot pin 19 in opposed relation to the yoke 18 and extending endwise into the guide frame 10 by which it is guided for longitudinal reciprocatory movements toward and away from the drive roll 4. This stem, in the present instance, is U-shape in cross-section with the inner or yoke ends of its side walls perforated and receiving the pivot pin 19 to have transverse movements therewith (Fig. 4), and is also rigidly fixed to the frame 20. The web portion of the stem 26 is provided at its inner end with an inwardly projecting ear 27 to receive the inner end thrust of a coiled expansion spring 28 mounted lengthwise in the stem. A pin 29 projects from the car 27 into the adjacent spring end to serve as a centering means therefor.

The outer end thrust of the spring 28 is against the closed rear end part 30 of a channel member 31 that projects into the channel of the stem 26 from its outer or rear end and has its web or closed side opposed to that of the stem. The channel member 31 is freely movable in the stern channel lengthwise thereof and its channel, inwidth, is preferably slightly greater than the diameter of the spring coil (Fig. 4). The channel member 31, which may be termed a tension release member for the spring 28, has a pair of transversely spaced ears 32 at its inner end, or that adjacent to the yoke 18, which project laterally therefrom through an opening 33 in the cover plate 13 on the guide frame 10 (Fig. 5). The member 31 is thus permitted to move lengthwise of the guide 10 the length of said opening and thereby relieve, to some extent at least, the outward pressure of the spring 28 against the frame 20. This permits inward movement of the yoke 18 and its roll 5 to facilitate placing on and removal of a sanding belt 3 from the rolls.

A control for the releasing movement of the member 31 comprises a lever 35 that is pivoted at its rear end to the guide frame 10 at 36 and is connected by a link 37 to the ears 32 of the member 31. This provides a toggle connection between the guide frame and tension release member 31, which, when straightened, as in Fig. 3 and as shown in full line position in Fig. 5, holds the frame 20 and its yoke 18 in belt tensioning position. When the lever 35 is thrown outward the tensioning member 31 is moved rearward to relieve the pressure of the spring 28 against the frame 20.

We wish it understood that our invention is not limited to any specific construction, arrangement or form of the parts, as it is capable of numerous modifications and changes without departing from the spirit of the claims.

What we claim is:

1. In a sanderplane having spaced apart drive and idler rolls with the latter movable transversely toward and away from the other, and a sanding belt guide by said rolls, the provision of a fixed guide between said rolls, a frame having a stem projected into and guided for movements by said guide toward and away from said idler roll, a frame fixedly carried by said stem at its outer end, a yoke carrying said idler roll and attached to said frame in opposition to said stem, a coiled expansion spring at a side of said stem and having one end applying an outward thrust to said frame, a member movable lengthwise of said guide and stem and opposing the end thrust of said spring in opposition to said frame, and means connected to said member and operable to move the member to apply or release the pressure of the spring on said frame to facilitate placing on or removing of a bell from said rolls.

2. In a surface abrading machine having a power driven roll, an idler roll spaced transversely of the power roll, an abrading belt connecting and guided by said rolls, and a yoke carrying said idler roll, the provision of a frame carrying said yoke for movements toward and away from the other roll, said frame having a stem projecting therefrom toward said other roll, a guide mounting said stem for longitudinal reciprocatory movements in the plane of said rolls, a coiled expansion spring disposed lengthwise of said plane and adapted to exert pressure at one end against said frame away from said drive roll, and means receiving the opposite end thrust of said spring and movable lengthwise of the spring relative to said guide, and means connected to said last means and operable to apply or relieve the spring pressure against said frame.

3. In a surfacing machine of the class described having transversely spaced drive and idler rolls, the idler roll being movable toward and away from the other roll, and an abrading belt connected and guided by said rolls, the provision of a guide lengthwise between said rolls, a stern projecting into and guided by said guide lengthwise thereof, means attached to one end of said stem and carrying said idler roll, a coiled expansion spring disposed lengthwise of said stem and having one end thrust against said means, a member reciprocally movable lengthwise of the stem and guide and receiving the thrust of the other end of said spring, and means connected to and manually operable to move said member to vary the spring pressure against said first means.

4. In a surfacing machine of the class described having transversely spaced drive and idler rolls, the idler roll being movable toward and away from the other, an abrading belt connecting and guided by said rolls, the provision of a fixed guide channel lengthwise between said rolls, a stem of channel form in cross-section reciprocally mounted in and guided by said guide channel, means attached to the outer end of said stem and carrying said idler roll, a coiled expansion spring disposed lengthwise in said stern channel and having one end thrust against said means, a member mounted in said stem channel and receiving a portion at least of said spring and having a part in thrust coaction with the rear end of the spring, said member being movable lengthwise of the spring and stem to relieve or apply tension to the spring in opposition to said means, and lever means connected to said guide and member and operable to impart movements to the member lengthwise of the spring.

References Cited in the file of this patent 

